Mechanical Degradation Model of Porous Fe Scaffold: Simulation Approach

Abstract

This paper proposes a simple degradation model that estimates morphological changes in pure iron scaffolding due to surface erosion. The main contribution of this work is to estimate the degradation of porous pure iron scaffolding and analyze the impact of morphological changes on mechanical properties. In this study, the pure iron scaffolding model was designed in CAD software with 3 different porosity such as 30%, 41%, and 55% respectively. The geometry images of CAD models with a resolution of 3316 x 5530 pixels are captured layer by layer with a thickness of 0.02 mm. The purpose of this method is to replace the function of the u-CT scanning technique. Two-dimensional morphological erosion is applied to reduce the number of pixels of the image model. This erosion process is adjusted iteratively with increasing number of pixels to erode the image model until the volume of the scaffold after reconstruction matches the volume of the model undergoing mathematical calculations. Their changes in the volume of scaffold geometry and degradation of mechanical properties were evaluated using finite element analysis. This study found that mechanical properties such as elastic modulus and yield strength decreased systematically during the 19 week degradation period. In addition, deformation analysis is performed on models based on finite element analysis.